RADIOBIOLOGYANDRADIATION PROTECTION(RT 106)

Course Title: RADIOBIOLOGY ANDRADIATION PROTECTION (RT 106)

Course Description:

Deals with the study of the effects of ionizing radiation on biological matters, the principles of radiation protection as well as agencies and institutions mandated to regulate and monitor the safe use of radiation and radioisotope in medicine.

Course Objectives:

At the end of the course, student is expected to understand the basic concept of radiation interaction as it relates to radiation biology and protection.

COURSE OUTLINE:

Review of Basic Radiation Conceptsll. Radiation Biology lll. Radiation Protection

COURSE OUTLINE:

Review of Basic Radiation Concepts

Radiation Biology

lll. Radiation Protection

RADIOBIOLOGY

Is the science dealing with the study of the effects of IONIZING RADIATION (x-rays, gamma rays & beta particles) on biologic tissue or living organisms.

X-RAYSGAMMARAYS

The following are the some effects of excessive IONIZING RADIATION exposure. MOIST DESQUAMATIONCATARACTEPILATIONCONGENITAL MALFORMATION

RADIATION PROTECTIONIs the science and practice of protecting the people (radiation workers, members of the public, and patients undergoing radiologic medical imaging procedures & radiation therapy) against the harmful effects of ionizing radiation.

RADIOGRAPHYRADIOTHERAPY

PART 1.

REVIEW OF BASIC RADIATION CONCEPT

What is RADIATION?

RADIATIONIs the energy emitted, travelled, and transferred through space and material in the form of rays, waves and particles.

Medical UltrasoundX-Rays

Beta Particles

EXAMPLE OF RADIATIONVISIBLE LIGHT radiated from the SUN, MICROWAVES from an OVEN, MEDICAL ULTRASOUND from DIAGNOSTIC ULTRASOUND MACHINE, X-RAYS from X-RAY MACHINE, GAMMA RAYS, ALPHA and BETA PARTICLES from RADIOACTIVE ATOMS (Thorium and Uranium).

TWO (2)CLASSIFICATION OF RADIATION

1.) NON-IONIZING RADIATION 2.) IONIZING RADIATION

CLASSIFICATION OF RADIATION

1.) NON-IONIZING RADIATION Is any kind of radiation for which the mechanism of action in biologic tissue does not directly ionize atomic or molecular system through a single interaction. This type of radiation has NO HARMFUL EFFECTS in biologic tissue of the human body.

NON-IONIZING RADIATION EXAMPLE: VISIBLE LIGHT radiated from the SUN, MEDICAL ULTRASOUND from DIAGNOSTIC ULTRASOUND MACHINE & RADIOFREQUENCY RAYS (Radio Waves and Magnetic Field) from MAGNETIC RESONANCE SCANNER.

VISIBLE LIGHT radiated from the SUN

MEDICAL ULTRASOUND from ULTRASOUND MACHINEMedical Ultrasound

RADIOFREQUENCY RAYS (Radio Waves and Magnetic Field) from MAGNETIC RESONANCE SCANNER

2.) IONIZING RADIATIONIs a special type of radiation that includes X-RAYS. IONIZING RADIATION is any kind of radiation capable of removing an orbital electron from the atom with which interacts.

X-RAYS

This type of radiation can GIVE HARMFUL EFFECTS in biologic tissue if it is absorbed more than the prescribed dose limit. MOIST DESQUAMATIONCATARACTEPILATIONCONGENITAL MALFORMATION

IONIZING RADIATIONExample: X-RAYS from X-RAY MACHINE, GAMMA RAYS from RADIOACTIVE ELEMENT COBALT 60 SOURCE (COBALT 60 TELETHERAPY MACHINE), ALPHA and BETA PARTICLES from RADIOACTIVE ATOMS (Thorium and Uranium).

X-RAYS from X-RAY MACHINEX-RAY TUBE

X-RAYS X-RAYS

RADIOGRAPHY

GAMMA RAYS from RADIOACTIVE ATOMS 60

GAMMA RAYS

RADIOTHERAPY COBALT 60 Source

GAMMA RAYS

ALPHA & BETA PARTICLES from RADIOACTIVE ATOMS (Thorium and Uranium)

Radioactive Atom/Element

NUCLEAR MEDICINE

IODINE 131

STRONTIUM 90

TWO (2) TYPES OF IONIZING RADIATION

1.) ELECTROMAGNETIC RADIATION 2.) PARTICULATE RADIATION

1.) ELECTROMAGNETIC RADIATION - is an oscillating electric and magnetic fields that travel in a vacuum with the velocity of light (186,000 miles/second). It includes X-rays, Gamma Rays, and some non-ionizing radiation (such as visible light, ultraviolet & infrared radiation, and radio waves. X-Rays Gamma Rays

X-RAYSAre penetrating, ionizing electromagnetic radiation that has a wavelength much shorter than that of visible light. It is also called photons androentgen rays.X-Rays X-Ray Tube

X-RAYS have a range of approximately 100 meters in AIR and 30 centimeters in TISSUE.

X-Rays X-Ray Tube

RADIOGRAPHY X-RAYS

X-RAYS are used to make or produce MEDICAL IMAGES of structuresand organs of the humanbody for DIAGNOSIS andTREATMENTof diseases. RadiographMammogramCT ScanMR Scan

RADIOGRAPHYCHEST X-RAY (Heart & Lungs)With the used of X-RAYS

MAMMOGRAPHY(X-RAY EXAMINATION)OF THE BREAST

With the used of X-RAYS

COMPUTED TOMOGRAPHY SCANNING(CT SCANNING)With the used of X-RAYS

CARDIOVASCULAR INTERVENTIONAL TECHNIQUEWith the used of X-RAYS

RADIOTHERAPY(LINEAR ACCELERATOR)With the used of HIGH-VOLTAGE X-RAYS

GAMMA RAYSAre penetrating, ionizing electromagnetic radiation of short wavelength emitted by the nucleus of radioactive atom (Cobalt 60) during its decay. Cobalt 60 60Radiotherapy

GAMMA RAYS are used in RADIOTHERAPY for the treatment of neoplasms (Cancer and Tumor). Cobalt Radiotherapy Cobalt 60

GAMMA RAYS have a range of approximately 100 meters in AIR and 30 centimeters in TISSUE.

Cobalt

COBALT 60 ( C) a radioisotope of the silver-white metallic element that emits high-energy gamma rays and is the most frequently used radio-isotope in RADIOTHERAPY.

Half-Life Form Administration

5.2 years External Machine (Cobalt Unit) (Teletherapy)6060

CESIUM 137 ( Cs) a radioactive atom that is used in RADIOTHERAPY as a sealed source of gamma rays intended for application to various malignancies that are treated by BRACHYTHERAPY.

Half-Life Form Administration

30.2 years In needles Interstitial Capsules Intra-cavitary 137

RADIO-FREQUENCY (RF) RAYS Are non-ionizing, electromagnetic radiation with frequencies from 0.3 kHz to 300 GHz; MAGNETIC RESONANCE IMAGING uses RF in the range of approximately 1 to 100 MHz.Cobalt

MEDICAL ULTRASOUNDAre sound waves at the very high frequency of over 20,000 vibrations per second used in ULTRASONOGRAPHY to visualize subcutaneous body structures including tendons, muscles, joints, vessels and internal organs for possible pathology or lesions and for fetal monitoring.

Cobalt

2.) PARTICULATE RADIATION are those radiation in particles emitted by the nucleus of a RADIO- ACTIVE ATOMS (Radionuclides or Radioisotopes) during its decay. It includes alpha and BETA Particles, electrons, neutrons, and protons.

Radioactive Atom

BETA PARTICLESAre particulate, ionizing radiation with characteristics of an electron emitted from the nucleus of RADIO-ACTIVE ATOMS (Radionuclides or Radioisotopes) during its radioactive decay. Beta particle have a range of approximately 10 meters in AIR and 12 centimeters in TISSUE.

BETA PARTICLES emitted by radioactive atoms (radionuclides or radioisotopes) are used in NUCLEAR MEDICINE for medical imaging and treatment of diseases.IODINE 131

STRONTIUM 90

Comparison of Alpha Particles, Beta Particles, Gamma Rays and X-Rays

How easily are four (4) common types of radiation (alpha, beta, gamma, and x-rays) STOPPED? The graphic above shows that alpha particle is stopped by a sheet of paper, skin and body tissues stops beta particles, but lead or concrete are required to stop gamma rays and x-rays.X-rays